An electrostatic discharge protection circuit and chip

Abstract

This application discloses an electrostatic discharge (ESD) protection circuit and chip. The ESD protection circuit includes a conversion module and a dissipation module. The conversion module is connected to a power supply and a ground terminal. The conversion module is configured to obtain a second voltage based on the first voltage when the first voltage provided by the power supply exceeds a threshold voltage. The threshold voltage is the voltage corresponding to the generation of ESD, and the second voltage is less than the first voltage. The dissipation module is connected to the output terminal of the conversion module and to the power supply and ground terminal. The dissipation module is configured to receive the second voltage, operate according to the second voltage, and modulate the first voltage to be less than the threshold voltage before outputting it to the electronic device. In other words, the technical solution of this application reduces the overvoltage corresponding to the generation of ESD through the conversion module and avoids drawing additional current, thereby protecting subsequent electronic devices from damage caused by ESD overvoltage. Furthermore, the structure is simple and the cost is reduced.

Description

Technical Field

[0001] This utility model relates to the field of integrated circuit technology, and in particular to an electrostatic protection circuit and chip. Background Technology

[0002] In the application of integrated circuits, with the increasing miniaturization and integration of electronic devices, the demand for devices with smaller size, higher integration and faster switching speed is rising. However, electrostatic discharge (ESD) events may damage electronic devices, leading to malfunctions or failures.

[0003] Current protection circuit designs typically employ RC (Resistor-Capacitor) networks, clamping circuits, and active detection circuits. Clamping circuits, however, can lead to issues such as clamping noise and reduced dynamic range due to the fixed clamping voltage of the ESD device, further shrinking the Safe Operating Area (SOA). This can degrade device performance and cause electrical overstress damage. Alternatively, RC networks can be used, but when a negative ESD pulse occurs between the device's input / output (I / O) pins and the power supply, the ESD detection circuit generates an overvoltage at the gate port, damaging the ESD shunt circuit and causing dielectric breakdown. Furthermore, additional leakage current can reduce the performance and lifespan of electronic devices. Moreover, these circuits are prone to false triggering due to noise or other transient events, potentially leading to accidental discharge and further damage. Therefore, current protection circuit designs are susceptible to damage, causing malfunctions or failures and affecting the normal operation of electronic devices. Utility Model Content

[0004] The technical solution to the main technical problem solved by this utility model is to provide an electrostatic protection circuit and chip that can effectively eliminate the impact of electrostatic discharge events on electronic devices, thereby protecting the electronic devices and enabling them to operate normally.

[0005] To solve the above-mentioned technical problems, one technical solution adopted in this application is: providing an electrostatic discharge (ESD) protection circuit, which is disposed between a power supply and an electronic device. The ESD protection circuit includes: a conversion module and a dissipation module. The conversion module is connected to the power supply and to ground. The conversion module is configured to obtain a second voltage based on the first voltage when the first voltage provided by the power supply exceeds a threshold voltage, wherein the threshold voltage is the voltage corresponding to the generation of static electricity, and the second voltage is less than the first voltage. The dissipation module is connected to the output terminal of the conversion module and to the power supply and ground. The dissipation module is configured to receive the second voltage, operate according to the second voltage, and modulate the first voltage to be less than the threshold voltage before outputting it to the electronic device.

[0006] To solve the above-mentioned technical problems, another technical solution adopted in this application is to provide a chip including the above-mentioned electrostatic protection circuit.

[0007] Unlike current technologies, the electrostatic discharge (ESD) protection circuit provided in this application is positioned between the power supply and the electronic device. The ESD protection circuit includes a conversion module and a dissipation module. The conversion module is connected to the power supply and to ground. The conversion module is configured to obtain a second voltage based on the first voltage when the first voltage supplied by the power supply exceeds a threshold voltage. The threshold voltage is the voltage corresponding to the generation of static electricity, and the second voltage is less than the first voltage. The dissipation module is connected to the output terminal of the conversion module and to both the power supply and ground. The dissipation module is configured to receive the second voltage, operate according to the second voltage, and modulate the first voltage to be less than the threshold voltage before outputting it to the electronic device. This is the technical solution of this application. Because current technical solutions may generate ESD due to noise or other transient events, the resulting overvoltage can easily cause potential damage to the electronic device. Therefore, this application uses a conversion module to reduce the overvoltage corresponding to the generation of static electricity and a dissipation module to modulate the overvoltage to a normal voltage, avoiding the extraction of additional current, thereby protecting the subsequent electronic device from damage caused by the overvoltage of ESD. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0009] Figure 1 This is a schematic diagram of the structure of the first embodiment of the electrostatic protection circuit in this application;

[0010] Figure 2 This is a schematic diagram of the structure of the second embodiment of the electrostatic protection circuit in this application;

[0011] Figure 3 This is a schematic diagram comparing the simulation curves of the two architectures under negative ESD pulse excitation in the first embodiment of this application;

[0012] Figure 4 This is a schematic diagram comparing the simulation curves of the two architectures under positive ESD pulse excitation in the first embodiment of this application.

[0013] Figure 5 This is a schematic diagram of the structure of the third embodiment of the electrostatic protection circuit in this application;

[0014] Figure 6 This is a schematic diagram comparing the simulation curves of the two architectures under negative ESD pulse excitation in the second embodiment of this application;

[0015] Figure 7 This is a schematic diagram of the structure of one embodiment of the chip in this application.

[0016] In the attached diagram, the components include: electrostatic protection circuit 10, conversion module 100, detection submodule 110, first detection unit 111, first resistor 1111, second resistor 1112, second detection unit 112, isolation submodule 120, isolation unit 121, first isolation subunit 1211, second isolation subunit 1212, third isolation subunit 1213, control unit 122, first control subunit 1221, second control subunit 1222, drive unit 123, first drive subunit 1231, second drive subunit 1232, dissipation module 200, dissipation unit 210, and chip 20. Detailed Implementation

[0017] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It is understood that the specific embodiments described herein are only for explaining this application and not for limiting it. Furthermore, it should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings, not all structures. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0018] The reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0019] The steps in the embodiments of this application are not necessarily processed in the order described. The steps can be rearranged, deleted, or added as needed. The step descriptions in the embodiments of this application are only optional combinations of sequences and do not represent all possible combinations of steps in the embodiments of this application. The order of steps in the embodiments should not be considered as a limitation of this application.

[0020] The terms "first," "second," etc., used in this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0021] Current protection circuits typically employ RC (Resistor-Capacitor) networks, clamping circuits, and active detection circuits. Clamping circuits can lead to issues such as clamping noise and reduced dynamic range due to the fixed clamping voltage of the ESD device, as well as a narrowed Safe Operating Area (SOA), potentially degrading device performance and causing electrical overstress damage. Alternatively, RC networks can be used, but when a negative ESD pulse occurs between the device's input / output (I / O) pins and the power supply, the ESD detection circuit generates an overvoltage at the gate port, damaging the ESD shunt circuit and causing dielectric breakdown. Furthermore, additional leakage current can reduce the performance and lifespan of electronic devices. Moreover, these circuits are prone to false triggering due to noise or other transient events, potentially leading to accidental discharge and further damage to the electronic device. Therefore, current protection circuit solutions are susceptible to damage, causing malfunctions or failures and affecting the normal operation of electronic devices.

[0022] Therefore, an electrostatic discharge (ESD) protection circuit is provided, which reduces the overvoltage corresponding to the generation of static electricity through a conversion module and avoids the extraction of additional current, and then eliminates the static electricity through a dissipation module, thereby protecting subsequent electronic equipment from damage caused by the overvoltage of electrostatic discharge.

[0023] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of the first embodiment of the electrostatic protection circuit in this application.

[0024] like Figure 1As shown, the electrostatic discharge protection circuit 10 is disposed between the power supply and the electronic equipment. The electrostatic discharge protection circuit 10 includes a conversion module 100 and a dissipation module 200.

[0025] The conversion module 100 is connected to a power supply and to ground. The conversion module 100 is configured to obtain a second voltage based on the first voltage when the first voltage supplied by the power supply exceeds a threshold voltage. The threshold voltage is the voltage corresponding to the generation of static electricity. Preferably, the second voltage is less than the first voltage.

[0026] Here, "power supply" refers to the power source that supplies power to electronic devices. "Electronic devices" refers to electronic devices that are functioning normally, such as consumer electronics, automotive electronics, industrial electronics, and other related electronic devices in various fields. "Conversion module 100" refers to a functional module that can detect the first voltage provided by the power supply and obtain a second voltage based on the first voltage; "threshold voltage" refers to the voltage corresponding to the generation of static electricity, that is, the maximum value of the normal voltage in the circuit when static electricity is generated, which can be set according to actual conditions.

[0027] The dissipation module 200 is connected to the conversion module 100, and is also connected to the power supply and ground (GND). The dissipation module 200 is configured to receive a second voltage, operate according to the second voltage, and modulate the first voltage to a value less than a threshold voltage before outputting it to the electronic device.

[0028] The dissipation module refers to a module that can reduce the first voltage, that is, eliminate static electricity, while maintaining a normal voltage output to electronic devices.

[0029] Specifically, the electrostatic discharge (ESD) protection circuit 10 is located between the power supply and the electronic device, specifically connected in parallel between the power supply and ground terminals of the electronic device. The conversion module 100 detects the first voltage supplied by the power supply and determines whether the first voltage exceeds a threshold voltage. If the first voltage exceeds the threshold voltage, it indicates that the current first voltage is an overvoltage corresponding to the generation of static electricity. To prevent damage to subsequent electronic devices from the first voltage, the conversion module 100 obtains a second voltage based on the first voltage exceeding the threshold voltage and outputs the second voltage to the dissipation module 200. The dissipation module 200 receives the second voltage output by the conversion module 100, operates on the second voltage, and modulates the first voltage to be less than the threshold voltage before outputting it to the electronic device to safely drive its operation.

[0030] In some embodiments, the conversion module 100 includes a detection submodule 110 and an isolation submodule 120. The detection submodule 110 is connected to a power supply and a ground terminal; one end of the detection submodule 110 is connected between the power supply and the electronic device, and the other end is connected to ground. The detection submodule 110 is configured to detect and receive a first voltage provided by the power supply. The isolation submodule 120 is connected to the detection submodule 110 and to both the power supply and ground terminal. The isolation submodule 120 is configured to, when the first voltage exceeds a preset threshold, obtain a second voltage based on the first voltage and output the second voltage to the dissipation module 200 through the output terminal of the conversion module 100.

[0031] In this embodiment, an electrostatic discharge (ESD) protection circuit is provided. The circuit reduces the overvoltage corresponding to the generation of static electricity through a conversion module and avoids the generation of additional current. The static electricity is then eliminated through a dissipation module, thereby protecting subsequent electronic equipment from damage caused by the overvoltage of electrostatic discharge.

[0032] In some embodiments, the electrostatic protection circuit may have a second embodiment.

[0033] See Figure 2 , Figure 2 This is a schematic diagram of the structure of the second embodiment of the electrostatic protection circuit in this application.

[0034] like Figure 2 As shown, the electrostatic discharge (ESD) protection circuit 10 is disposed between the power supply and the electronic device, specifically, the ESD protection circuit 10 is connected in parallel between the power supply and ground terminals of the electronic device. The ESD protection circuit 10 includes a conversion module 100 and a dissipation module 200. The conversion module 100 includes a detection submodule 110 and an isolation submodule 120, wherein the detection submodule 110 is connected to the power supply and ground terminals, that is, one end of the detection submodule 110 is connected between the power supply and the electronic device, and the other end of the detection submodule 110 is connected to the ground terminal. The detection submodule 110 is configured to detect a first voltage provided by the power supply. The isolation submodule 120 is connected to the detection submodule 110 and is connected to the power supply and ground terminals, wherein the isolation submodule 120 is configured to, when the first voltage exceeds a preset threshold, obtain a second voltage based on the first voltage, and output the second voltage to the dissipation module 200 through the output terminal of the conversion module 100.

[0035] In this context, the isolation submodule 120 refers to a module used to regulate the first voltage supplied by the power supply. The detection submodule 110 refers to a module capable of detecting and receiving the first voltage supplied by the power supply. In some embodiments, the detection submodule 110 can also be a module for filtering signals, such as attenuating high-frequency signals in the circuit, i.e., filtering.

[0036] Specifically, the first terminal of the isolation submodule 120 is connected between the power supply and the electronic device, the second terminal of the isolation submodule 120 is connected to the detection submodule 110, the third terminal of the isolation submodule 120 is connected to the ground terminal, and the isolation submodule 120 is also connected to the dissipation module 200 through a fourth terminal, which serves as the output terminal of the conversion module 100. The first terminal of the detection submodule 110 is connected to the power supply, the second terminal of the detection submodule 110 is connected to the second terminal of the isolation submodule 120, and the third terminal of the detection submodule 110 is connected to the ground terminal. The combined function of the detection submodule 110 and the isolation submodule 120 is to detect and receive the first voltage corresponding to the generation of static electricity. When the first voltage exceeds a preset threshold, a second voltage is obtained based on the first voltage, a portion of the reduced voltage flows to the ground terminal, and the second voltage is then output to the dissipation module 200 through the output terminal of the conversion module 100. This allows the dissipation module 200 to clamp the second voltage to a safe voltage not higher than that of the electronic device, thereby modulating the first voltage to be less than the threshold voltage before outputting it to the electronic device.

[0037] In this embodiment, the conversion module includes a detection submodule and an isolation submodule. When the detection submodule detects the first voltage corresponding to the generation of static electricity, the isolation submodule can effectively obtain the second voltage based on the overvoltage corresponding to the generation of static electricity. That is, the second voltage is obtained based on the first voltage, and the second voltage is greater than the activation voltage of the dissipation module and less than the safe voltage that the dissipation module can withstand, so as to avoid damage to the dissipation module.

[0038] Continue reading Figure 2 In some embodiments, the isolation submodule 120 may further include an isolation unit 121, a control unit 122, and a drive unit 123.

[0039] Isolation unit 121 is connected to detection submodule 110, wherein isolation unit 121 is configured to reduce the first voltage to a second voltage when the first voltage exceeds a preset threshold; control unit 122 is connected to isolation unit 121, and is also connected to power supply and ground, i.e., one end of control unit 122 is connected between power supply and electronic equipment, the other end of control unit 122 is connected to ground, and another end of control unit 122 is connected to isolation unit 121; control unit 122 is configured to control the on and off of voltage conversion of electrostatic protection circuit. Drive unit 123 is connected to isolation unit 121, and is also connected to voltage and ground, and drive unit 123 is connected to dissipation module 200; wherein drive unit 123 is configured to drive and activate dissipation module 200 using the second voltage.

[0040] Among them, the isolation unit 121 refers to the functional unit that obtains the second voltage based on the first voltage, the control unit 122 refers to the functional unit that controls the opening and closing of the voltage conversion of the electrostatic protection circuit, and the drive unit 123 refers to the functional unit that drives the dissipation module. Through the joint action of the isolation unit 121 and the control unit 122, the second voltage is obtained from the overvoltage corresponding to the generation of static electricity, that is, the second voltage is obtained based on the first voltage, and the dissipation module 200 is driven and activated by the drive unit 123 using the second voltage.

[0041] In this embodiment, through the joint action of the isolation unit and the control unit, the second voltage is obtained based on the first voltage, and then the second voltage is output to the dissipation module by the drive unit to ensure that the subsequent dissipation module is not damaged.

[0042] In some embodiments, the control unit 122 may include a first control subunit 1221 and a second control subunit 1222.

[0043] The first and second terminals of the first control subunit 1221 are connected to the power supply, and the third terminal of the first control subunit 1221 is connected to the first terminal of the second control subunit 1222. The second terminal of the second control subunit 1222 is connected to the ground terminal, and the third terminal of the second control subunit 1222 is connected to the isolation unit 121.

[0044] Furthermore, the first control subunit 1221 can be a gate control transistor, such as a P-type gate control transistor, and the second control subunit 1222 can also be a gate control transistor, such as an N-type gate control transistor. Then, the first terminal of the first control subunit 1221 is the source of the gate control transistor, the second terminal of the first control subunit 1221 is the drain of the gate control transistor, and the third terminal of the first control subunit 1221 is the gate of the gate control transistor; the first, second, and third terminals of the second control subunit 1222 are configured the same as those of the first control subunit 1221.

[0045] In some embodiments, the isolation unit 121 may include a first isolation subunit 1211 and a second isolation subunit 1212.

[0046] Specifically, the first end of the first isolation subunit 1211 is connected to the first end of the second isolation subunit 1212 and is also connected to the detection submodule 110; the second end of the first isolation subunit 1211 is connected to the second end of the second isolation subunit 1212, and the third end of the first isolation subunit 1211 is connected to the third end of the first control subunit 1221 in the control unit 122. The third end of the second isolation subunit 1212 is connected to the third end of the second control subunit 1222 of the control unit 122, and the first end of the second isolation subunit 1212 is also connected to the third end of the second isolation subunit 1212.

[0047] Furthermore, the first isolation subunit 1211 can be a switching transistor, such as a P-type switching transistor, and the second isolation subunit 1212 can also be a switching transistor, such as an N-type switching transistor. Thus, the first terminal of the first isolation subunit 1211 is the source of the switching transistor, the second terminal of the first isolation subunit 1211 is the drain of the switching transistor, and the third terminal of the first isolation subunit 1211 is the gate of the switching transistor; while the first, second, and third terminals of the second isolation subunit 1212 can have the same configuration as the first isolation subunit 1211.

[0048] Furthermore, the isolation unit 121 may also include a third isolation subunit 1213.

[0049] The first end of the third isolation subunit 1213 is connected to the first end of the second isolation subunit 1212 and is connected to the detection submodule 110; the second end of the third isolation subunit 1213 is connected to the first end of the first isolation subunit 1211, and the third end of the third isolation subunit 1213 is connected to the first end of the first isolation subunit 1211.

[0050] It is understood that the second and third ends of the third isolation subunit 1213 are connected, and the connection fulcrum here is connected to the first end of the first isolation subunit 1211; and the third isolation subunit 1213 can be a switching transistor, such as a P-type switching transistor; the first, second and third ends of the third isolation subunit 1213 can be the same as the first isolation subunit 1211.

[0051] In some embodiments, the driving unit 123 may include a first driving subunit 1231 and a second driving subunit 1232.

[0052] In this configuration, the first end of the first driving subunit 1231 is connected to the first end of the second driving subunit 1232, the second end of the first driving subunit 1231 is connected to the power supply, and the third end of the first driving subunit 1231 is connected to the isolation unit 121. The second end of the second driving subunit 1232 is connected to ground, and the third end of the second driving subunit 1232 is connected to the isolation unit 121. Furthermore, the fulcrum connecting the first end of the first driving subunit 1231 and the first end of the second driving subunit 1232 serves as the output terminal of the conversion module 100, and the output terminal is connected to the dissipation module 200.

[0053] Specifically, the second end of the first drive subunit 1231 is connected between the power supply and the electronic device, the third end of the first drive subunit 1231 is connected to the second end of the first isolation subunit 1211 in the isolation unit 121, and is also connected to the second end of the second isolation subunit 1212; while the third end of the second drive subunit 1232 is connected to the third end of the second isolation subunit 1212 in the isolation unit 121.

[0054] Furthermore, the first driving sub-unit 1231 can be a gate driving transistor, such as a P-type gate driving transistor, and the second driving sub-unit 1232 can also be a gate driving transistor, such as an N-type gate driving transistor. Therefore, the first terminal of the first driving sub-unit 1231 can be the source of the gate driving transistor, the second terminal of the first driving sub-unit 1231 can be the drain of the gate driving transistor, and the third terminal of the first driving sub-unit 1231 can be the gate of the gate driving transistor; the configuration of the first, second, and third terminals of the second driving sub-unit 1232 can be the same as that of the first driving sub-unit 1231.

[0055] In some embodiments, the detection submodule 110 may include a first detection unit 111 and a second detection unit 112.

[0056] The first end of the first detection unit 111 is connected to the power supply, and the second end of the first detection unit 111 is connected to the third end of the second detection unit 112; the first end and the second end of the second detection unit 112 are connected to the ground.

[0057] Specifically, the first end of the first detection unit 111 is connected between the power supply and the electronic device.

[0058] Furthermore, the first detection unit 111 may include at least two resistors connected in series; for example, it may include a first resistor 1111 and a second resistor 1112, in which case the first resistor 1111 and the second resistor 1112 are connected in series.

[0059] Furthermore, the second detection unit 112 can be a MOS capacitor, such as an N-type MOS capacitor. Then, the first terminal of the second detection unit 112 is the source of the MOS capacitor, the second terminal of the second detection unit 112 is the drain of the MOS capacitor, and the third terminal of the second detection unit 112 is the gate of the MOS capacitor.

[0060] In this system, the source, drain, and ground of a MOS capacitor are shorted together to form the lower stage, while the gate of the MOS capacitor forms the upper stage. When the voltage of the upper stage exceeds the threshold voltage of the MOS capacitor, an inversion layer will appear between the source and drain, forming a channel. The gate oxide layer in the MOS capacitor then acts as the insulating dielectric layer between the gate and the channel, thus forming the MOS capacitor.

[0061] In some embodiments, the dissipation module 200 may include a dissipation unit 210.

[0062] The first end of the dissipation unit 210 is connected to the power supply, the second end of the dissipation unit 210 is connected to the ground, and the third end of the dissipation unit 210 is connected to the output of the conversion module 100.

[0063] Specifically, the first end of the dissipation unit 210 is connected between the power supply and the electronic device, and the third end of the dissipation unit 210 is connected to the connection fulcrum of the first end of the first drive subunit 1231 and the first end of the second drive subunit 1232 in the conversion module 100.

[0064] Furthermore, the dissipation unit 210 can be a MOS transistor, such as an N-type MOS transistor. Then, the first terminal of the dissipation unit 210 is the source of the MOS transistor, the second terminal of the dissipation unit 210 is the drain of the MOS transistor, and the third terminal of the dissipation unit 210 is the gate of the MOS transistor.

[0065] The following describes the working principle of the electrostatic discharge (ESD) protection circuit.

[0066] The electrostatic discharge protection circuit 10 includes a conversion module 100 and a dissipation module 200; the conversion module 100 includes an isolation submodule 120 and a detection submodule 110; the isolation submodule 120 includes a control unit 122, an isolation unit 121, and a drive unit 123; the control unit 122 includes a first control subunit 1221 and a second control subunit 1222, wherein the first control subunit 1221 is a P-type gate control transistor and the second control subunit 1222 is an N-type gate control transistor; the isolation unit 121 includes a first isolation subunit 1211, a second isolation subunit 1212, and a third isolation subunit 1213, wherein the first isolation subunit 1211 is a P-type switching transistor. The second isolation subunit 1212 is an N-type switching transistor, and the third isolation subunit 1213 is a P-type switching transistor; the driving unit 123 includes a first driving subunit 1231 and a second driving subunit 1232, wherein the first driving subunit 1231 is a P-type gate driving transistor, and the second driving subunit 1232 is an N-type gate driving transistor; the detection submodule 110 includes a first detection unit 111 and a second detection unit 112; the first detection unit 111 includes a first resistor 1111 and a second resistor 1112, wherein the second detection unit 112 is an N-type MOS capacitor; the dissipation module 200 includes a dissipation unit 210, which is an N-type MOS transistor.

[0067] When a negative ESD pulse is applied between the power supply and ground, the second drive subunit 1232, the second control subunit 1222, the first isolation subunit 1211, the third isolation subunit 1213, and the second isolation subunit 1212 are closed. First, the isolation unit 121 isolates the ESD pulse coupled from the power supply. At the same time, the second detection unit 112 and the second control subunit 1222, together with the parasitic capacitances of the second isolation subunit 1212 (Cgs), the third isolation subunit 1213 (Cgd), and the first isolation subunit 1211 (Cgd and Cgs), can form a series-parallel capacitor network. This network then transmits the safety-regulated voltage level pulse, i.e., the second voltage, to the gates of the first isolation subunit 1211 and the first drive subunit 1231. The first drive subunit 1231 then turns on and activates the dissipation unit 210.

[0068] Furthermore, since the gate voltages of the first driving subunit 1231 and the first isolation subunit 1211 are inversely proportional, that is:

[0069] Vgmp1=[Cgsmn3 / (Cgsmn3+Cgsmp3)]*(Vrc-Vgmp3).

[0070] Wherein, Vgmp1 is the gate voltage of the first driving sub-unit, Cgsmn3 is the gate-source capacitance of the second isolation sub-unit 1212, Cgsmp3 is the gate-source capacitance of the first isolation sub-unit 1211, Vgmp3 is the gate voltage of the first isolation sub-unit 1211, and Vrc is the rectified voltage, which is also the second voltage.

[0071] The third isolation subunit 1213 can be used to reduce the parasitic capacitance from the drain to the gate of the first isolation subunit 1211, thereby obtaining a larger voltage drop and reducing the overvoltage risk of the first drive subunit 1231.

[0072] In some embodiments, multiple isolation sub-units can be connected in series to reduce parasitic capacitance. In this embodiment, a first isolation sub-unit 1211 connected in series with a third isolation sub-unit 1213 is used as an example for illustration. Furthermore, it is understood that the parasitic capacitance of the second driving sub-unit 1232 is much smaller than that of the second filtering unit, and therefore can be ignored.

[0073] Therefore, the technical solution of this application effectively solves the problem of excessively high gate port level when a negative ESD pulse is applied between the power supply and ground, preventing over-stress and ensuring reliable operation of electronic equipment. It also reduces the ESD area. Furthermore, the modulation voltage and RC frequency detection in this application aim to improve the reliability and robustness of the electrostatic protection circuit, preventing false triggering due to noise or other transient events.

[0074] When a positive ESD pulse is applied between the power supply and ground, the first driving subunit 1231 reduces the transmission of the positive ESD pulse to activate the dissipation unit 210. The second detection unit 112 is connected between the power supply and the output terminal VG of the conversion module 100. The output terminal VG of the conversion module 100 can be the parasitic capacitance of the dissipation unit 210. The function of the resistor connected from the output terminal VG of the conversion module 100 of the ESD circuit to the power supply is to establish the voltage level required to activate the dissipation unit 210, which can be achieved by a voltage clamping circuit.

[0075] Therefore, the second detection unit 112 is charged by the first detection unit 111, and VRC changes from 0 to Vclamp. The second drive subunit 1232, the second control subunit 1222, the first isolation subunit 1211, the third isolation subunit 1213, and the second isolation subunit 1212 are initially turned off. However, when VRC is greater than the Vth of a MOS diode and after an RC delay, they can conduct, and then the first drive subunit 1231 is turned off. At this time, due to the delay of the isolation submodule 120, the area of ​​the second detection unit 112 can be reduced, thereby reducing cost and size, and thus enabling the electrostatic protection circuit to obtain a larger drain discharge current.

[0076] Furthermore, a comparison was made using simulated curves.

[0077] Please see Figure 3 , Figure 3 This is a schematic diagram comparing the simulation curves of the two architectures under negative ESD pulse excitation in the first embodiment of this application.

[0078] like Figure 3 As shown, in this embodiment, ID_ESDN is the value of the discharge current of the dissipation unit 210 in this embodiment, in amperes; in the conventional embodiment, ID_ESDN is the current value of the discharge current in the conventional method; in this embodiment, VG_INVP is the value of the gate voltage of the driving unit 123 in this embodiment, in volts; in the conventional embodiment, VG_INVP is the voltage value of the gate voltage in the conventional method; in this embodiment, VG_ESDN is the voltage value of the discharge voltage of the dissipation unit 210 in this embodiment, in volts; in the conventional embodiment, VG_ESDN is the voltage value of the discharge voltage in the conventional method.

[0079] Depend on Figure 3 As can be seen, compared with the traditional method, this application increases the discharge current of the dissipation unit 210, increases the gate voltage of the dissipation unit 210, and increases the discharge voltage of the dissipation unit, thus solving the problem of excessively high gate port level of the dissipation unit 210, preventing overstress, and ensuring reliable operation of the protection circuit. At the same time, it reduces the ESD area, effectively preventing false triggering due to noise or other transient events.

[0080] Figure 3 For the specific values ​​in the table, please refer to the first table, as follows:

[0081]

[0082]

[0083] First table

[0084] Please see Figure 4 , Figure 4 This is a schematic diagram comparing the simulation curves of the two architectures under positive ESD pulse excitation in the first embodiment of this application.

[0085] like Figure 4 As shown, in this embodiment, ID_ESDN is the value of the discharge current of the dissipation unit 210 in this embodiment, and the unit is amperes; in the conventional method, ID_ESDN is the value of the discharge current in the conventional method; the results show that the electrostatic protection circuit of this application can obtain a larger drain discharge current.

[0086] Depend on Figure 4 It is understood that the protection circuit of this application can obtain a larger discharge current at the drain port, thereby improving the ability of the dissipation unit 210 to quickly release electrostatic charge and avoid damage to electronic equipment due to instantaneous high voltage.

[0087] Figure 4 The values ​​for are shown in Table 2, as follows:

[0088] This embodiment uses ID_ESDN Traditional ID_ESDN Time (nanoseconds) Electric current (amperes) Electric current (amperes) 0 0 0 1 0.53 0.53 2 1.06 1.06 5 2.27 1.97 10 2.74 2.54 15 2.86 2.66 20 2.84 2.66 25 2.79 2.61 30 2.70 2.54 35 2.59 2.46 40 2.48 2.37 45 2.37 2.28 50 2.26 2.18 55 2.14 2.08 60 2.02 1.98 65 1.90 1.88 70 1.80 1.78 75 1.69 1.68 80 1.60 1.59 85 1.51 1.5 90 1.42 1.41 95 1.34 1.33 100 1.25 1.25 105 1.18 1.18 110 1.11 1.11 115 1.04 1.04 120 0.98 0.98 125 0.92 0.92 130 0.86 0.86 135 0.81 0.81 140 0.76 0.76 145 0.71 0.71 150 0.67 0.67 155 0.63 0.63

[0089] Second Table

[0090] Under normal operating conditions, i.e., when there is no ESD pulse, the leakage current of the ESD circuit is in the picoampere range. At this time, the second drive subunit 1232 and the second detection unit 112 close the dissipation unit 210, the first drive subunit 1231 is in the off state, while the second control subunit 1222, the first isolation subunit 1211, the third isolation subunit 1213, and the second isolation subunit 1212 operate normally. Under these conditions, the leakage current of the electrostatic protection circuit is extremely small, ensuring stable and reliable operation of the internal circuitry even in environments with high electromagnetic interference.

[0091] The following description is based on simulation results.

[0092] Assuming the electronic device is an IOPAD and the AVDD50 is the power supply, the simulation uses a -5kV human body model (HBM) generator, which applies a negative ESD pulse with a peak current of -3.3339A to the two terminals between the IOPAD and AVDD50. The electrostatic discharge (ESD) protection circuit of this application effectively clamps the ESD voltage to a safe level (-1.0914V), lower than the current structure (-9.6296V), thereby preventing damage to the gate driver, i.e., preventing damage to the drive unit. Similarly, the ESD protection circuit of this application also clamps the gate of the dissipation unit 210 to -5.279V, lower than the current structure (-10.29V), preventing damage to the dissipation unit 210.

[0093] In this embodiment, the isolation submodule and the filtering submodule in the conversion module reduce the first voltage corresponding to the generation of static electricity and avoid drawing out additional current, and output a second voltage. Then, the static electricity is eliminated by the dissipation module, and the first voltage is modulated to be less than the threshold voltage before being output to the electronic device, thereby protecting the subsequent electronic device from being damaged by the overvoltage of electrostatic discharge.

[0094] The electrostatic discharge protection circuit in this application may also have a third embodiment.

[0095] Please see Figure 5 , Figure 5 This is a schematic diagram of the third embodiment of the electrostatic protection circuit in this application.

[0096] like Figure 5 The above, with Figure 2 The same parts will not be repeated here. Figure 2The difference is that the driving unit 123 may include: a first driving subunit 1231 and a second driving subunit 1232.

[0097] In this configuration, the first end of the first driving subunit 1231 is connected to the first end of the second driving subunit 1232, the second end of the first driving subunit 1231 is connected to the power supply, and the third end of the first driving subunit 1231 is connected to the isolation unit 121. The second end of the second driving subunit 1232 is connected to the ground, and the third end of the second driving subunit 1232 is connected to the third end of the first driving subunit 1231 and also connected to the second end of the first isolation subunit 1211 of the isolation unit 121, i.e., connected to the second end of the second isolation subunit 1212 of the isolation unit 121. Furthermore, the fulcrum connecting the first end of the first driving subunit 1231 and the first end of the second driving subunit 1232 serves as the output end of the conversion module 100, and the output end is connected to the dissipation module 200.

[0098] Specifically, the second end of the first drive subunit 1231 is connected between the power supply and the electronic device, and the third end of the first drive subunit 1231 is connected to the second end of the first switch unit in the isolation unit 121; while the third end of the second drive subunit 1232 is connected to the third end of the first drive subunit 1231.

[0099] The simulation results are used for description.

[0100] Please see Figure 6 , Figure 6 This is a schematic diagram comparing the simulation curves of the two architectures under negative ESD pulse excitation in the second embodiment of this application.

[0101] like Figure 6 As shown, in this embodiment, ID_ESDN is the value of the discharge current of the dissipation unit 210 in this embodiment, in amperes; in the conventional embodiment, ID_ESDN is the current value of the discharge current in the conventional method; in this embodiment, VG_INVP is the value of the gate voltage of the driving unit 123 in this embodiment, in volts; in the conventional embodiment, VG_INVP is the voltage value of the gate voltage in the conventional method; in this embodiment, VG_ESDN is the voltage value of the discharge voltage of the dissipation unit 210 in this embodiment, in volts; in the conventional embodiment, VG_ESDN is the voltage value of the discharge voltage in the conventional method.

[0102] according to Figure 6As can be seen, compared with the traditional method, this application increases the discharge current and gate voltage of the dissipation unit 210, thereby solving the problem of excessively high gate port level of the dissipation unit 210, preventing overstress, and ensuring the reliable operation of the protection circuit. It also reduces the ESD area. Furthermore, it effectively prevents false triggering due to noise or other transient events.

[0103] Figure 6 The values ​​in the table are shown in the third table, and the specific values ​​are as follows:

[0104]

[0105] Third Form

[0106] In addition, in comparison Figure 4 and Figure 6 The electrostatic protection circuit of the second embodiment improves the gate voltage glitches problem of the electrostatic discharge tube, that is, it improves the gate voltage glitches problem of the dissipation unit 210.

[0107] In this embodiment, the principle is the same as that of the first embodiment, and the corresponding technical effects are also the same, so they will not be repeated here; the difference is that the gates of the first driving sub-unit 1231 and the second driving sub-unit 1232 are connected together to reduce the delay and make the delay problem disappear.

[0108] The above technical solution provides an electrostatic discharge protection circuit that reduces the overvoltage corresponding to the generation of static electricity through a conversion module and avoids drawing out additional current, thereby protecting subsequent electronic equipment from damage caused by the overvoltage of electrostatic discharge. It also has a simple structure, reduces costs, and has wide applicability.

[0109] See Figure 7 , Figure 7 This is a schematic diagram of the structure of one embodiment of the chip in this application, as shown below. Figure 4 As shown, a chip 20 is provided, including the electrostatic discharge protection circuit 10 described above.

[0110] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the system implementations described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, apparatuses, or units, and may be electrical, mechanical, or other forms.

[0111] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0112] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0113] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0114] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. An electrostatic protection circuit, characterized by comprising: The electrostatic discharge (ESD) protection circuit is disposed between the power supply and the electronic equipment, and the ESD protection circuit includes: A conversion module is connected to the power supply and to ground. The conversion module is configured to obtain a second voltage based on the first voltage when the first voltage provided by the power supply exceeds a threshold voltage, wherein the threshold voltage is the voltage corresponding to the generation of static electricity, and the second voltage is less than the first voltage. A dissipation module is connected to the output terminal of the conversion module and to the power supply and ground terminal. The dissipation module is configured to receive the second voltage, operate according to the second voltage, and modulate the first voltage to be less than the threshold voltage before outputting it to the electronic device.

2. The electrostatic discharge protection circuit according to claim 1, characterized in that, The conversion module includes: A detection submodule is connected to the power supply and the ground terminal, wherein the detection submodule is configured to detect a first voltage provided by the power supply; An isolation submodule is connected to the detection submodule and to the power supply and ground. The isolation submodule is configured to obtain the second voltage based on the first voltage when the first voltage exceeds a preset threshold, and output the second voltage to the dissipation module through the output terminal of the conversion module.

3. The protection circuit according to claim 2, characterized in that, The isolation submodule includes: An isolation unit is connected to the detection submodule, wherein the isolation unit is configured to obtain the second voltage based on the first voltage when the first voltage exceeds a preset threshold. A control unit, connected to the isolation unit, and connected to the power supply and the ground terminal, wherein the control unit is configured to control the electrostatic protection circuit to turn on and off voltage conversion; A driving unit is connected to the isolation unit, the power supply and the ground terminal, and the driving unit is connected to the dissipation module, wherein the driving unit is configured to drive and activate the dissipation module using the second voltage.

4. The electrostatic protection circuit according to claim 3, characterized in that, The control unit includes: A first control subunit, wherein a first terminal and a second terminal of the first control subunit are connected to the power supply; The second control subunit has a first end connected to the third end of the first control subunit, a second end connected to the ground terminal, and a third end connected to the isolation unit.

5. The electrostatic protection circuit according to claim 3, characterized in that, The isolation unit includes: A first isolation subunit, the first end of which is connected to the detection submodule, and the third end of which is connected to the third end of the first control subunit of the control unit; The second isolation subunit has a first end connected to the first end of the first isolation subunit and connected to the detection submodule. The second end of the second isolation subunit is connected to the second end of the first isolation subunit. The third end of the second isolation subunit is connected to the third end of the second control subunit of the control unit. The first end of the second isolation subunit and the third end of the second isolation subunit are also connected. The third isolation subunit has a first end connected to the first end of the second isolation subunit, a second end connected to the first end of the first isolation subunit, and a third end connected to the first end of the first isolation subunit.

6. The electrostatic protection circuit according to claim 3, characterized in that, The driving unit includes: A first driving subunit, the second end of which is connected to the power supply, and the third end of which is connected to the second end of the first isolation subunit of the isolation unit; The second driving subunit has a first end connected to the first end of the first driving subunit, a second end connected to ground, and a third end connected to the third end of the second isolation subunit of the isolation unit. The fulcrum connecting the first end of the first driving subunit and the first end of the second driving subunit serves as the output end of the conversion module, and the output end of the conversion module is connected to the dissipation module.

7. The electrostatic discharge protection circuit according to claim 3, characterized in that, The driving unit includes: A first driving subunit, the second end of which is connected to the power supply, and the third end of which is connected to the second end of the first isolation subunit of the isolation unit; The second driving subunit has a first end connected to the first end of the first driving subunit, a second end connected to ground, and a third end connected to the third end of the first driving subunit. The fulcrum connecting the first end of the first driving subunit and the first end of the second driving subunit serves as the output end of the conversion module, and the output end of the conversion module is connected to the dissipation module.

8. The electrostatic protection circuit according to claim 2, characterized in that, The detection submodule includes: A first detection unit, wherein a first terminal of the first detection unit is connected to the power supply; The second detection unit has a first end and a second end connected to the ground terminal, and a third end connected to the second end of the first detection unit.

9. The electrostatic discharge protection circuit according to claim 1, characterized in that, The dissipation module includes: The dissipation unit has a first end connected to the power supply, a second end connected to the ground, and a third end connected to the output of the conversion module.

10. A chip, characterized by An electrostatic protection circuit comprising the circuit according to any one of claims 1 to 9.

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